1. Field of the Invention
The present invention relates to a weather strip for providing a seal between an opening portion of a vehicle body and a closing member for closing the opening portion, such as a vehicle door, a luggage door, a sliding roof, etc.
2. Description of Related Art
FIG. 1 is a cross-sectional view of a conventional sealing structure between a door opening portion of a vehicle body and a vehicle door. As shown, to provide a seal between a door opening portion 10 and a vehicle door 12, a door weather strip 14 is attached to a retainer 16 provided along an outer periphery of a door frame, a glass run 18 is attached to a channel 20 provided along an inner periphery of the door frame, and a door opening trim weather strip 22 is attached to a flange 24 projecting from the door opening portion 10. The flange 24 is formed by joining end edges of an outer body panel 26 and an inner body panel 28 of the vehicle body.
The glass run 18 includes an outer side wall 30, a bottom wall 32 and an inner side wall 34, and has a generally U-shaped cross-section. When a door glass 36 is raised, an end of the door glass 36 enters an interior of the glass run 18, and is sealed with an outer seal lip 38 and an inner seal lip 40 extending from open ends of the outer side wall 30 and the inner side wall 34, respectively.
The door weather strip 14 attached to the outer periphery of the door 12 includes a base portion 42, a tubular seal portion 44 integrally formed on the base portion 42, and a seal lip 46. The base portion 42 is secured to the door frame by fitting the base portion 42 in the retainer 16 provided along the outer periphery of the door frame. When the door 12 is closed, the seal lip 46 contacts an outer end of the door opening portion 10 and the tubular seal portion 44 contacts a protruding part of the door opening portion 10 on the inner side of the contacting position of the seal lip 46 to provide a seal between the door opening portion 10 and the vehicle door 12.
The door opening trim weather strip 22 attached to the flange 24 provides a seal between the door opening portion 10 and the vehicle door 12 on the inner side of the contacting position of the tubular seal portion 44 of the door weather strip 14. The door opening trim weather strip 22 includes a base portion 48 having a U-shaped cross-section and a tubular seal portion 50. The base portion 48 is attached to the flange 24 and the tubular seal portion 50 contacts a protruding part 52 of the door frame to provide a seal between the door opening portion 10 and the vehicle door 12. An insert member 54 such as a metal insert, etc. is embedded in the base portion 22, and lips are provided in the base portion 48 for holding the flange 24.
In many cases, the door opening trim weather strip 22 is attached over the entire circumference of the door opening portion 10. The number of body panels forming the flange 24 depends on the position in the door opening portion 10 and varies from two to five, and consequently, the thickness of the flange 24 varies from about 2 mm to about 8 mm.
Therefore, where the base portion 48 has a generally U-shaped section and the metal insert member 54 is embedded for holding the flange 24, the force required for inserting the flange 24 may increase or the holding force against the flange 24 may decrease according to the attaching position. In this case, the weight of the door opening trim weather strip 22 increases so as not to respond to the demand for the decrease in the vehicle weight.
Under the above-described circumstances, as shown in FIG. 2, there has been also carried out the method of removing the insert member such as the metal insert from a base portion 56 to enhance the flexibility thereof, and attaching the resultant flexible base portion 56 to the flange 24 using a double-sided adhesive tape 58 (see Publications of unexamined Japanese patent applications Nos. 2001-151035 and 2002-137695, ex.).
In this case, the double-sided adhesive tape 58 is bonded to an interior surface of an outer side wall 60 of the base portion (trim portion) 56, the flange 24 is inserted in an interior of the trim portion 56, and the double-sided adhesive tape 58 is pressed against an exterior surface of the flange 24.
In another case shown in FIG. 3, one side wall of a trim portion 62 is formed short, a double-sided adhesive tape 64 is bonded to a longer side wall of the trim portion 62, a projecting end of the flange 24 is inserted in a bottom of an interior of the trim portion 62, and the trim portion 62 is turned in the direction of the arrow to bond the double-sided adhesive tape 64 to the flange 24 (see U.S. Pat. No. 3,180,493, ex.).
However, where the metal insert is removed as described above, the extensibility in the longitudinal direction of the door opening trim weather strip increases. Consequently, when the door opening trim weather strip is attached along the door opening portion, the door opening trim weather strip elongates and it may lift from the flange in the door opening portion, or generate wrinkles. In addition, there arises the problem that the dimensions of products may vary due to the remaining stress in the manufacturing step, the temperature change in the assembling step, the elongation and shrinkage occurring during the storage of the products, etc., thereby causing the door opening trim weather strip to lift from the door opening portion or to generate wrinkles.
And upon bonding the door opening trim weather strip to the flange using the double-sided adhesive tape, a protecting tape is peeled from the adhesive tape, the flange is inserted in an interior of the trim portion, and the double-sided adhesive tape is pressed against a side surface of the flange. In this case, a projecting end of the flange may contact the double-sided adhesive tape to cause the peeling of the double-sided adhesive tape, or the flange may be undesirably bonded to the double-sided adhesive tape before inserted into a bottom of the trim portion.
And, as shown in FIG. 1, the flange 24 is formed by joining end edges of the outer body panel 26 and an inner body panel 28 to each other by welding or other method, and the outer body panel 26 and the inner body panel 28 define a cavity adjacently to the flange 24. Various noises such as wind noises, tire noises, road noises, etc. are transmitted over the entire circumference of the door opening portion via this cavity. There are formed protrusions and depressions in the flange 24 due to the spot welding or the sheet metal processing to define gaps between adjacent body panels. And the above-described noises leak via these gaps and are transmitted to a vehicle compartment.
In order to overcome this problem and improve the sealing properties around the flange 24, in the conventional example shown in FIG. 4, a sponge rubber 68 is attached to an interior of a trim portion 70 for contacting the projecting end of the flange 24 (see Publication of unexamined Japanese patent application No. 2000-219048 and Publication of unexamined Japanese utility model application No. Sho 54-31622, ex.).
In this example, a holding lip 72 provided in the interior of the trim portion 70 holds the flange 24, and the projecting end of the flange 24 merely contacts an interior surface of the sponge rubber 68. Therefore, the positioning of the projecting end of the flange 24 is insufficient so that sufficient sealing properties cannot be effected between the projecting end of the flange 24 and the sponge rubber 68.